Apparatus for making embossing cylinders



Feb. 6, 1934. F. FISCHER 1,945,935

APPARATUS FOR MAKING EMBOSSING CYLINDERS Filed 001;. 22, 1931 INVENTOR ATTORNE Patented Feb. 6, 1934 UNITED STATES v i-eur- OFFICE APPARATUS FOR MAKING EMBOSSING CYLINDERS Application October 22, 1931 Serial No.' 570,340, and in Germany December 18, 1930 5 Claims. (Cl. 29-90) This invention relates to a novel and improved apparatus and method for forming embossing cylinders, particularly such cylinders as are used for embossing films of the so-called .goffered" type used in the well-known Berthon process of color photography. The novel features will be bestunderstood from the following description and the annexed drawing, in which I have shown a selected embodiment of the apparatus by which the method may be practiced, and in which:

Fig. l is a diagrammatic elevation of the essential parts of an apparatus which may be used in the practice of the invention.

Fig. 2 is a fragmentary section through the cylinder appearing in Fig. 1 and taken at right angles to Fig. 1, this view being on a greatly enlarged scale.

Fig. 3 is a view similar to Fig. 2, but showing the grooves in thecylinders following a further step inthe method.

Fig. 4 is a view on the line 4-4 of Fig. 1, with the wire omitted.

Fig. 5 is a section on the line 55 of Fig.4.

The so-called goiiered type of film is used and made with a multiplicityof fine cylindrical elements extending lengthwise of the film, these elements being on the order of some 700 to the inch. To insure correct results, each element should be truly cylindrical and meet adjoining elements along sharply defined edges formed by the intersection of truly cylindrical surfaces.

According to my invention, the above result is attained by an apparatus and method which will now be described.

Referring first to Fig. 1, I have shown therein an embossing cylinder 1 mounted in .a turning lathe, the details of the lathe being omitted as they form no part of the novel features of the invention. On opposite sides of the cylinder are placed reels 2 and 3, upon which is mounted a wire 4. This wire extends between the reels 2 and 3 and over the cylinder 1, being disposed in a groove in the face thereof. These grooves are indicated at 5 in Figs. 2 and 3. The cylinder is to be used to emboss the surface of a film in a manner well known in the art, this embossing being done by pressing the film against the surface of the cylinder, which surface is provided with circumferentially extending grooves. These grooves may be either, parallel to each other, or arranged on the spiral extending lengthwise of the cylinder, and are closely spaced, being of the order of some 700 to the inch.

The grooves may first be formed in therough, as indicated in Fig. 2, this being done by any suitable tool or apparatus, such as that illustrated, for example, in the patent to Brosse 1,703,026. Then the wire 4 is used for polishing, and, according to this invention, the polishing is done by drawing the wire from one reel to the other; for example, from the reel 2 to the reel 3, while rotating the cylinder 1 in the direction indicated by the arrow. Preferably, the winding-on reel 3 is positively driven, which may be accomplished by the gearing indicated generally at '6 5 and connecting the turning lathe direct to the reel 3. Because of the difference in diameters between the cylinders 1 and the reels, it will be seen that the speed at which the wire moves is ,difierent from the speed of the movement given 10 to the surface of the cylinder 1, if they were moving in the same direction. In this instance, the speed of the wire is less than that of the cylinder surface, which indeed is here moving in the opposite direction.

I provide guides '7 and Son opposite sides of the cylinder which serve to hold the wire in correct position with respect to the grooves. One of these guides through which the wire passes before contactir; with the cylinder is preferably formed so with a draw-hole 9 as indicatedin Figs. 4 and 5. This hole may be cut in some hard substance, such as a diamond, indicated at 10. The hole 9 is of the exact form which the wire should have in order to polish the grooves to the exact shape required.

The operation will be plain from the above description, but may be briefly summarized. The cylinder 1 is secured in the turning lathe and caused to rotate by any suitable means. Such means may comprise the shaftupon which the cylinder is mounted, or the shaft of any of the gearing 6. Assuming that the cylinder is turned in the direction indicated by the arrow, the wire will be drawn in the direction indicated, that is, from right to left of Fig.1 1, and at a differ ent speed from that taken by thesurface of the cylinder. As the wire passes through the drawhole 9, it will be given a cylindrical form of a radius exactly that required for the grooves. It is of course understood, as noted above, that the grooves have been roughed out by any suitable means. such as cutting, pressing, or etching. If desired, suitable polishing material may be placed in the grooves for operation with the wire 4 as it passes therethrough. In case the grooves are continuous, forming a spiral extending lengthwise of the-cylinder, as is common in the art, the cylinder 1 may be given a movement parallel to its axis so that the wire will follow along in the 110 grbove until the operation is completed. If, on the other hand, separate grooves exactly parallel to each other and formed on true circumferences of the cylinder are used, then obviously no such travel of the cylinder is provided, but in that case it is wires 4 so as to polish several grooves at once. Suilicient drag is placed upon the wire, either by the reel 2 or by the draw-hole, or both, so as to keep the wire taut where it engages the cylinder.

The above arrangement has several advantages, among which may be mentioned the fact that the polishing wire is not used up rapidly as is the case with other prior art devices intended to use wire in polishing cylinders of this character. In such devices, the wire is short and is rapidly worn so that it does not keep its initial and desired cross section. Moreover, such devices do not provide any means for maintaining the desired form of the wire.

The life of the wire may be further prolonged by performing the polishing operation in several steps, as, for example, by rotating the cylinder l'and moving the wire 4 at such relative speeds that one rotation of the cylinder will not cause a complete polishing of the grooves. In this way, the wear on the wire is distributed over a greater length of wire, and so any given length will maintain its correct form for a longer period of time.

While I have shown the invention as embodied in a specific form, it is to be understood that various changes in details may be made without departing from the scope of the invention, and I therefore do not intend to limit myself except by the appended claims.

I claim:

1. In a device for forming an embossing cylinder, means for rotating said cylinder, a polishing wire engaging a groove in the surface of said cylinder, means for moving the wire through the groove at a diflerent speed from that of said surface, and a guide adjacent said cylinder having a hole through which the wire passes, said feasible to use a plurality of' hole having edges of material harder than that of the wire and conforming in shape to the desired form of the groove in the wire to the same form.

2. In a device for forming an embossing cylinder, reels disposed on opposite sides 01' the cylinder, a polishing wire extending from one to the other transversely to the axis of the cylinder, with a portion thereof disposed in a circumferentially extending groove in said cylinder, means forrotating said cylinder on its axis, and means for winding the wire from one reel to the other through said groove.

3-. In a device for forming an embossing cylinder, reels disposed on opposite sides or the cylinder, a polishing wire wound on said reels and extending from one to the other transversely to the axis of the cylinder, with a portion thereof disposed in a circumferentially extending groove in said cylinder, means for rotating said cylinder on its axis, and means for winding the wire from'one reel to the other through said groove at a speed different from that 01 the speed at which the groove is moving.

4. In a device for forming an embossingcylthe cylinder, to draw wound on said reels andv inder, means for rotating said cylinder, reels disposed on opposite sides of the cylinder, a polishing wire wound on said reels and extending from one tothe other, with a portion thereof disposed in a groove insaid cylinder, means for roand means for winding the to the other through said different from that of the groove is moving and in the tating said cylinder, wire from one reel groove at a speed speed at which the opposite direction.

5. In a device for forming an embossing cylinder, means for movably supporting a polishing wire in position transversely of the axis of the cylinder, with a portion thereof disposed in a circumferentially extending groove in said cylinder, means for continuously moving said wire lengthwise in said groove, and means for rotating said cylinder on its axis during said movement of the wire'in said groove.

FRITZ FISCHER. 

